Double fuze for hand grenades



March 28, 1967 F. BERGER 3,311,059

DOUBLEFUZE FOR HAND GRENADES Filed Dec. 8, 1964 4 Sheets-Sheet 1 Fig.2

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March 28, 1967 F, BERGER 3,311,059

DOUBLE FUZE FOR HAND GRENADES Filed Dec. 8, 1964 4 Sheets-Sheet 5 lm enfor: 'Z B5 99,-

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Filed Dec. 8, 1964 United States Patent Cfifice 331L059 Patented Mar. 28, 1967 3,311,059 DOUBLE FUZE FOR HAND GRENADES Fritz Berger, Dusseldorf, Germany, assignor toFirma Rheinmetall G.m.b.H., Dusseldorf, Germany Filed Dec. 8, 1964, Ser. No. 416,760 Claims priority, applicatigg Gsgrmany, Dec. 18, 1963,

6 Claims. 61. 102-74 pact ignition is located. On impact of the hand grenade, the igniting needle pierces a primer capsule on displacement of the percussion pieces and this results in explosion of the hand grenade.

Known fuzes of this type 'are not entirely satisfactory, however, since on the one hand they are of too complicated construction and thereby prone to trouble and relatively costly and, on the other hand, it has been found that they frequently do not oifer sufiicient sensitivity or safety in handling.

The problem on which the invention is based is to provide an adjustable double fuze for hand grenades which, on the one hand, obviates the drawbacks mentioned and which, moreover, also has relatively small dimensions which enable a larger explosive charge to be accommodated in the explosive body. Furthermore, the design of the double fuze should be kept simple, so as to render economic manufacture possible.

According to the invention the percussion pieces, which are formed 'as mirror images one of the other and are symmetrical, are spaced from one another and positioned in a cylindrical recess in the fuze body disposed transversely of the longitudinal axis of the fuze body, the impact-ignition needle and a primer capsule being arranged in the percussion pieces on the longitudinal axis thereof in manner known per se, and that on the one hand a pin held by the safety band is provided between the percussion bodies as an impact safety device and on the other hand a locking member likewise held by the band and resting externally against the fuze body is provided in manner known per se, the said locking member dropping after the band has been released and thereby freeing a rotary striker arranged to swing transversely of the longitudinal axis of the fuze body for initiating the delay ignition.

The locking member which may. rest against the outer wall of the fuze body is advantageously in the form of a flat slide which is displaceable by the twisting, known per se, of the setting device in opposition to the force of the safety band'ernbracing the said flat slide, the latter having a groove or the like which frees the rotary striker for starting the delay fuze after the slide has been actuated.

This feature likewise assists to a considerable extent in meeting the requirement of simplicity in the design of the fuze.

To suit a particular requirement, the fuze can be set either for non-delay ignition or for delay ignition. With the non-delay setting, the grenade detonates on impact but, in addition, a delay composition or train burns away in known manner and produces detonation if the impact fuze should fail for any reason. With the delay setting, impact ignition is excluded and detonation is initiated by burning away of the delay composition or train.

Furthermore, according to a subsidiary feature of the invention, the setting device of the fuze is formed by a transport safety cap known per se and which surrounds the fuze during transport and storage. Setting of the fuze to the kind of ignition desired at any given time, namely either non-delay ignition or delay ignition, is effected by merely twisting this cap. In this way, a substantial simplification in the handling of the hand grenade is also obtained.

Finally, the handling safety and also the ease of handling of the hand grenade are improved in a simple and adv'antagteou's manner in that, in addition to the rotary striker for initiating the delay ignition being secured by the locking member in the form of a fiat slide, it is also secured by an auxiliary locking means which is released when the grenade leaves the hand throwing it. The auxiliary locking means may consist, preferably, of 'a yoke formed as a gripping support and which rests externally against the grenade body and is embraced by the throwing hand and which also engages as a bolt in a recess in 'the rotary striker.

In this way it is possible, first, to hold a grenade which has already been set to delay ignition for throwing in the hand until a favourable moment for throwing occurs, since the auxiliary locking means is not released until the grenade leaves the throwing hand and, second, the setting device can be turned back to the transport position again if the grenade is not to be thrown.

In a preferred embodiment of the invention, the handling safety is increased by providing, on the outside of the fuze body, flexible strips overlapping the safety band, these strips being each attached to the fuze body at one end only. This has the advantage that a grenade which has already been set for non-delay throwing and has inadvertently fallen out of the throwers hand cannot become live through release of the band, because the strips overlapping the bandprevent such release.

Details of the embodiments of the invention are explained in the following description with reference to the accompanying drawings of which:

FIG. 1 is a longitudinal section of a double fuze,

FIG. 2 is a cross-section on the line IIII of FIG. 1,

FIG. 3 is a section of the fuze on the line IIIIII in FIG. 2, and shows the fuze mounted on a grenade,

FIG. 4 is a view, on a smaller scale, of the grenade and fuze as seen in the direction of the arrow IV in FIG. 3,

FIG. 5 is a View in the direction of the arrow IV of FIG. 3 of the auxiliary locking means, and,

FIGS. 6 and 7 are sections corresponding to FIG. 3 and FIG. 2 of a modified constructional form of the fuze.

The reference 1 designates the body of a double fuze, which can be screwed by means of a threaded stub 2 into the body 3 of a hand grenade. A primer capsule 4 and a detonator 5 are arranged in the threaded stub 2. A cap 6 which is mounted over the fuze serves as storage and transport safety means, the cap reliably sealing the fuze system and the explosive charge by means of an inserted packing ring 7. Two pins 22 are arranged opposite one another in the bottom edge of the transport cap at the periphery thereof and engage corresponding grooves 24 provided in a collar 23 of the fuze body, whereby the cap is held on the fuze body. The transport cap 6 also forms a setting device for the fuze. Setting is effected by twisting the transport cap in one direction or the other, as indicated in FIG. 4. For non-delay setting, the cap is twisted out of the transport or safety position (see FIG. 4) and removed, while in the case of delay setting the cap is twisted in the opposite direction and is left in this position, that is, is not removed. This is rendered possible by the design of the grooves 24 provided in the collar 23 of the fuze body. As will be seen in FIG. 3, the grooves 24 ascend from a bottom point Tthe trans port position of the cap 6-on both sides of the point. There is a groove ascending with a shallow slope towards the position mV (delay) and another ascending with a steeper slope towards the position V (non-delay), where the groove terminates at the top edge of the collar 23. When the fuze is set at 0V, the pins move from the transport position T in the grooves, the hold of the cap being released to permit the cap to be removed upwardly (as seen in FIG. 1). On setting to mV, i.e. when the cap is turned in the opposite direction, the cap cannot be removed, since the groove is closed at this point. Mistakes in handling thus seldom occur since the lifting of the cap away from the grenade body in the 0V position is initiated automatically by the relaxing packing ring 7. The transport cap moreover has a marking member 25 which projects from the fuze body which also makes setting possible in darkness. In the transport position, the marking member 25 is located opposite a corresponding marker member, for example a stud 26 or the like, which is arranged on the grenade body or on a gripping support bearing against the body.

The construction of the impact fuze itself is as follows:

Two mirror-image percussion pieces 9 and 10 are spaced from one another in a horizontal cylindrical recess 8 disposed transversely of the longitudinal axis of the fuze body 1. The convex outer ends of the pieces are urged against conical supporting surfaces 12 and 13 in the chamber 8 by a coil spring 11 exerting only a small force. On the longitudinal axis of the percussion bodies, a primer capsule 14 is arranged in one body 9 and an impact-ignition needle 15 is arranged in the other body 10, the tip of the ignition needle extending to a point just in front of the primer capsule. The impact fuze operates in the known manner and will not be described further.

As shown in FIG. 3, a pin 16 is disposed in the f-uze body with the head 17 of the pin mounted in a bore in the body open on the outside. The pin 16 is held by a retaining safety band 19 in opposition to the pressure of a spring 18. The safety band is wound round the fuze body several times in the conventional manner and its free end is furnished with a gripping support 20 which promotes the release or unwinding of the band and acts as a centrifugal element. This gripping support 20 bears closely against the body of the hand grenade and is secured by the transport safety cap 6. Moreover, an elastic transport ring 41 is also provided which clamps the gripping support tightly against the grenade body and is pulled off before the grenade is thown. The pin 16 projects into a space 21 between the two percussion pieces 9 and 10 and, since its diameter is adapted to the width of the gap 21, prevents premature impact ignition. This can take place only when, after the safety band has unwound, the pin is ejected by the spring 18. In comparison with the centrifugal weights which are customarily employed in other cases, the gripping support 20 has the advantage that the unwinding of the band begins with greater certainty immediately after release. However, this occurs only when the transport cap has been removed, i.e. when the grenade is thrown with the fuze set at 0V.

The delay fuze is constructed as follows:

In a recess 27 in the head of the fuze body a rotary striker 28 is mounted rot-atably on a pivot 38. The rotary striker is loaded by a torsion spring 29 and is held in the loaded condition (FIG. 1) by a flat slide 30 which is thus a locking slide. The flat slide 30 rests against the outside of the fuze body and is retained by the band 19. Moreover, an auxiliary locking means in the form of a bolt or yoke member 39 is provided and is arranged to be movable longitudinally on the gripping support 20, serving as a centrifugal weight. In the secure or safe position, the bolt 39 engages in a corresponding recess 28' in the rotary striker (FIG. 2), in which it is held by the force of a spring 40 which is attached to the gripping support. After a hand grenade set at 0V has been released, the bolt 39 first releases the rotary striker, whereupon after the band 19 has unwound the slide 30 drops, whereby the last obstacle in the way of the rotary striker 28 has been removed. The latter rotates under the force of its loading spring 29 and its point 31 pierces the primer capsule 32 of a delay composition or train 33. After the composition has burned away the primer capsule 4 and the detonator 5 are ignited by way of a bore 34.

It may happen that a hand grenade which has already been set at non-delay ignition for throwing (that is for impact and delay ignition should the grenade fail to explode on impact) drops inadvertently out of the throwers hand. It is true that in this case the gripping support has lifted away from the hand grenade with the bolt 39, so that the first locking means for the rotary striker 28 has been removed, but unwinding of the band is prevented by flexible strips 37 mounted on the outside of the fuze body and overlapping the safety band. Detonation of the grenade therefore cannot occur, since the rotary striker is still secured by the flat slide 30. The impact fuze also cannot operate, because the pin 16 is still located between the two percussion pieces 9, 10. These strips 37 are thin, narrow sheet-metal or plastic strips which are each attached to the fuze body only at one end, and, in fact, alternately at one end or the other. The strips have such flexibility that they do not impede the unwinding of the band when the hand grenade is thrown.

To throw the hand grenade with delay ignition, the cap is twisted appropriately and remains in this position. Impact ignition is excluded in this case, since the safety band is not unwound and the safety pin 16 remains between the percussion pieces. The clearing of the looking means for the rotary striker in order to initiate the delay ignition is effected in the following manner:

When the cap 6 is turned to delay ignition, the fiat slide 30 resting against the outside of the fuze body is engaged by an adjusting cam 35 provided on the inside of the wall of the cap and shifted downwardly, so that a bend 36 in the slide passes into the region of the recess 27 in which the notary striker 28 is mounted so that the path of rotation thereof is cleared. However, the rotary striker is still held in its initial position by the bolt 39. By turning the cap back, the slide can be raised again by a corresponding cam 35 provided on the wall of the cap below the bend 36 and the rotary striker can hence be secured again.

During the setting operation, a thrower holds the grenade enclosed in his throwing hand, the gripping support 20 being embraced by the hand. In the construction shown in FIG. 3, a swivel lever 43 mounted pivotally on the gripping support at 42 is likewise held in this process against a spring 44. When the grenade leaves the throwing hand, the lever 43 swivels outwards, whereby the bolt 39 arranged movably on the gripping support and which is connected to the swivel lever 43 by a draw wire 45 is drawn downwardly out of the recess 28 pnovided in the rotary striker. The last means of holding the rotary striker against movement is thereby removed and the latter flies around its pivot under the force of its spring 29 and pierces the primer capsule 32:

In the construction shown in FIGS. 6 and 7, the gripping support 20 is formed as a double-armed lever which is mounted to be tiltable longitudinally of the grenade body in the region of :the packing ring 7 secured at the edge of the cap, this being achieved by means of a thickened portion 46 of the grenade body. The gripping support terminates at its upper end in a tongue 39' which engages in the manner of a bolt in a recess 28' in the rotary striker. If, when the cap is set at mV, that is with the cap 6 not removed, the grenadeis thrown, the gripping support tilts about the thickened portion 46 under theforce of a spring 47 arranged between it and the grenade body and the tongue 39' swings towards the longitudinal axis of the fuze, and the rotary striker is released.

What I claim is:

1. A double fuze for a hand grenade comprising in combination,.-a fuze body, a setting device removably attached to the body and having one position for delay ignition and a different position for impact and delay ignition, a releasable safety band wound round said body, a cylindrical recess disposed in said fuze body transversely of the longitudinal axis of said fuze body, two mirror image percussion pieces located symmetrically in spaced manner in said cylindrical recess, an impact needle mounted on one of said percussion pieces and a primer capsule mounted on the other percussion piece, a spacer pin located in part between said percussion pieces so as normally to hold said pieces in spaced relationship, said pin being retained in position by said band, a striker movably mounted on said fuze body, a delay ignition system located in said fuze body and operated by said striker on release thereof, a locking member for normally holding said striker against movement, said locking member also being held in position by said safety band, an auxiliary locking means for holding said striker against movement, and means for releasing said auxiliary locking means when said grenade is thrown.

2. A double fuze for a hand grenade comprising in combination, a fuze body, a setting device removably attached to the body and having one posit-ion for delay ignition and a different position for impact and delay ignition, a releasable safety band wound round said body, a cylindrical recess disposed in said fuze body transversely of the longitudinal axis of said fuze body, two mirror image percussion pieces located symmetrically in spaced manner in said cylindrical recess, an impact needle mounted on one of said percussion pieces and a primer capsule mounted on the other percussion piece, a spacer pin located in part between said percussion pieces so as normally to hold said pieces in spaced relationship, said pin being retained in position by said band, a striker movably mounted on said fuze body, a delay ignition system located in said fuze body and operated by said striker on release thereof, a slide member normally holding said striker against movement, said slide member being displaceable on movement of said setting device to said delay ignition position to release said striker, said slide member being otherwise held in position by said safety band, and a yoke member having a portion for holding said striker against movement and a further portion formed as a gripping support, said gripping support portion being located externally of said grenade and adapted to be embraced by the hand of a thrower.

3. A double f uze for a hand grenade comprising in combination, a fuze body, a setting device removably attached to the body and having one position for delay ignition and a different position for impact and delay ignition, a releasable safety ban-d wound round said body, a cylindrical recess disposed in said fuze body transversely of the longitudinal axis of said fuze body, two mirror image percussion pieces located symmetrically in spaced manner in said cylindrical recess, an impact needle mounted on one of said percussion pieces and a primer capsule mounted on the other percussion piece, a spacer pin locate-d in part between said percussion pieces so as normally to hold said pieces in spaced relationship, said pin being retained in position by said band, a striker movably mounted on said fuze body, a delay ignition system located in said fuze body and operated by said striker on release thereof, a slide member normally holding said striker against movement, said slide member being displaceable on movement of said setting device to said delay ignition position to release said striker, said slide member being otherwise held in position by said safety band, a longitudinally-displaceable yoke member having a portion for holding said striker against movement and a further portion formed as a gripping support and located externally of said grenade, a swivel lever mounted on said gripping support, and spring means acting on said swivel lever to cause the latter to displace said yoke member and permit movement of said striker when the grenade leaves a throwers hand.

4. A double fuze for a hand grenade comprising in combination, a fuze body, a setting device removably attached to the body and having one position for delay ignition and a different position for impact and delay ignition, a releasable safety band wound round said body, a cylindrical recess disposed in said fuze body transversely of the longitudinal axis of said fuze body, two mirror image percussion pieces located symmetrically in spaced manner in said cylindrical recess, an impact needle mounted on one of said percussion pieces and a primer capsule mounted on the other percussion piece, a spacer pin located in part between said percussion pieces so as normally to hold said pieces in spaced relationship, said pin being retained in position by said band, a striker movably mounted on said fuze body, a delay ignition system located in said fiuze body and operated by said striker on release thereof, a locking member for normally holding said striker against movement, said locking member also being held in position by said safety band, an auxiliary locking device for holding said striker against movement and for acting as a centrifugal weight for said safety band, and means for releasing said auxiliary locking device when said grenade is thrown.

5. A double fuze for a hand grenade comprising in combination, a fuze body, a setting device removably attached to the body and having one position for delay ignition and a different position for impact and delay ignition, a releasable safety band wound round said body, a cylindrical recess disposed in said fuze body transversely of the longitudinal axis of said fuze body, two mirror image percussion pieces located symmetrically in spaced manner in said cylindrical recess, an impact needle mounted on one of said percussion pieces and a primer capsule mounted on the other percussion pice, a spacer pin located in part between said percussion pieces so as normally to hold said pieces in spaced relationship, said pin being retained in position by said band, a striker movably mounted on said fuze body, a delay ignition system located in said fuze body and operated by said striker on release thereof, a locking member for normally holding said striker against movement, said locking member also being held in position by said safety band, flexible strips extending longitudinally of said fuze body and overlapping said releasab'le safety band, said stripsbeing attached at one end only externally to said fuze body.

6. A double fuze for a hand grenade comprising in combination, a fiuze body, a setting device removably attached to the body and having one position for delay ignition and a different position for impact and delay ignition, a releasable safety band wound round said body, a cylindrical recess disposed in said fuze body transversely of the longitudinal axis of said fuze body, two mirror image percussion pieces located symmetrically in spaced manner in said cylindrical recess, an impact needle mounted on one of said percussion pieces and a primer capsule mounted on the other percussion piece, a spacer pin located in part between said percussion pieces so as normally to hold said pieces in spaced relationship, said pin being retained in position by said band, a striker movably mounted on said f uze body, a delay ignition system located in said fuze body and operated by said striker on release thereof, a locking member for normally holding said striker against movement, said locking member also being held in position by said safety band, flexible strips extending longitudinally of said fuze body and overlapping said releasable safety band, alternate strips being attached externally to said fuze body at opposite ends.

O a) References Cited by the Examiner UNITED STATES PATENTS 11/1931 Perego 10273 5/1948 Fix 10271 X 7/1953 Knowlton 19281.6 12/1963 Urdapilleta 10281.6 X 9/1964 Varaud 10274 FOREIGN PATENTS 8/ 1918 Germany. 4/1962 Great Britain.

BENJAMIN A. BORCHELT, Primary Examiner.

15 G. H. GLANZMAN, Assistant Examiner. 

1. A DOUBLE FUZE FOR A HAND GRENADE COMPRISING IN COMBINATION, A FUZE BODY, A SETTING DEVICE REMOVABLY ATTACHED TO THE BODY AND HAVING ONE POSITION FOR DELAY IGNITION AND A DIFFERENT POSITION FOR IMPACT AND DELAY IGNITION, A RELEASABLE SAFETY BAND WOUND ROUND SAID BODY, A CYLINDRICAL RECESS DISPOSED IN SAID FUZE BODY TRANSVERSELY OF THE LONGITUDINAL AXIS OF SAID FUZE BODY, TWO MIRROR IMAGE PERCUSSION PIECES LOCATED SYMMETRICALLY IN SPACED MANNER IN SAID CYLINDRICAL RECESS, AN IMPACT NEEDLE MOUNTED ON ONE OF SAID PERCUSSION PIECES AND A PRIMER CAPSULE MOUNTED ON THE OTHER PERCUSSION PIECE, A SPACER PIN LOCATED IN PART BETWEEN SAID PERCUSSION PIECES SO AS NORMALLY TO HOLD SAID PIECES IN SPACED RELATIONSHIP, SAID PIN BEING RETAINED IN POSITION BY SAID BAND, A STRIKER MOVABLY MOUNTED ON SAID FUZE BODY, A DELAY IGNITION SYSTEM LOCATED IN SAID FUZE BODY AND OPERATED BY SAID STRIKER ON RELEASE THEREOF, A LOCKING MEMBER FOR NORMALLY HOLDING SAID STRIKER AGAINST MOVEMENT, SAID LOCKING MEMBER ALSO BEING HELD IN POSITION BY SAID SAFETY BAND, AN AUXILIARY LOCKING MEANS FOR HOLDING SAID STRIKER AGAINST MOVEMENT, AND MEANS FOR RELEASING SAID AUXILIARY LOCKING MEANS WHEN SAID GRENADE IS THROWN. 